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  • Javascript with Django?

    - by Rosarch
    I know this has been asked before, but I'm having a hard time setting up JS on my Django web app, even though I'm reading the documentation. I'm running the Django dev server. My file structure looks like this: mysite/ __init__.py MySiteDB manage.py settings.py urls.py myapp/ __init__.py admin.py models.py test.py views.py templates/ index.html Where do I want to put the Javascript and CSS? I've tried it in a bunch of places, including myapp/, templates/ and mysite/, but none seem to work. From index.html: <head> <title>Degree Planner</title> <script type="text/javascript" src="/scripts/JQuery.js"></script> <script type="text/javascript" src="/media/scripts/sprintf.js"></script> <script type="text/javascript" src="/media/scripts/clientside.js"></script> </head> From urls.py: (r'^admin/', include(admin.site.urls)), (r'^media/(?P<path>.*)$', 'django.views.static.serve', {'document_root': 'media'}) (r'^.*', 'mysite.myapp.views.index'), I suspect that the serve() line is the cause of errors like: TypeError at /admin/auth/ 'tuple' object is not callable Just to round off the rampant flailing, I changed these settings in settings.py: MEDIA_ROOT = '/media/' MEDIA_URL = 'http://127.0.0.1:8000/media'

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  • Regex: Matching a space-joined list of words, excluding last whitespace

    - by Jesper
    How would I match a space separated list of words followed by whitespace and some optional numbers? I have this: >>> import re >>> m = re.match('(?P<words>(\w+\s+)+)(?P<num>\d+)?\r\n', 'Foo Bar 12345\r\n') >>> m.groupdict() {'num': '12345', 'words': 'Foo Bar '} I'd like the words group to not include the last whitespace(s) but I can't figure this one out. I could do a .strip() on the result but that's not as much fun :) Some strings to test and wanted result: 'Foo & Bar 555\r\n' => {'num': '555', 'words': 'Foo & Bar'} 'Hello World\r\n' => {'num': None, 'words': 'Hello World'} 'Spam 99\r\n' => {'num': 99, 'words': 'Spam'} 'Number 1 666\r\n' => {'num': 666, 'words': 'Number 1'}

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  • installing simplejson on the google appengine

    - by user266564
    Super nub question time! I am trying to use simplejson on the google appengine. In a terminal on my machine I have simplejson installed and working. But my when I try to import it in a script running on the appengine I get an error saying no such library exists. If open the interactive console on my machine (from the link on http://localhost:8080/_ah/admin) and type "import simplejson" I get: Traceback (most recent call last): File "/home/chris/google_appengine/google/appengine/ext/admin/init.py", line 210, in post exec(compiled_code, globals()) File "", line 1, in ImportError: No module named simplejson Any thoughts?

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  • Parsing names with pyparsing

    - by johnthexiii
    I have a file of names and ages, john 25 bob 30 john bob 35 Here is what I have so far from pyparsing import * data = ''' john 25 bob 30 john bob 35 ''' name = Word(alphas + Optional(' ') + alphas) rowData = Group(name + Suppress(White(" ")) + Word(nums)) table = ZeroOrMore(rowData) print table.parseString(data) the output I am expecting is [['john', 25], ['bob', 30], ['john bob', 35]] Here is the stacktrace Traceback (most recent call last): File "C:\Users\mccauley\Desktop\client.py", line 11, in <module> eventType = Word(alphas + Optional(' ') + alphas) File "C:\Python27\lib\site-packages\pyparsing.py", line 1657, in __init__ self.name = _ustr(self) File "C:\Python27\lib\site-packages\pyparsing.py", line 122, in _ustr return str(obj) File "C:\Python27\lib\site-packages\pyparsing.py", line 1743, in __str__ self.strRepr = "W:(%s)" % charsAsStr(self.initCharsOrig) File "C:\Python27\lib\site-packages\pyparsing.py", line 1735, in charsAsStr if len(s)>4: TypeError: object of type 'And' has no len()

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  • getting keyboard events with pyqt

    - by Moayyad Yaghi
    hello i converted recently from wxpython to pyqt and im still facing alot of problems since im still noob in pyqt so is it possible to detected if user pressed (CTRL+key ) in pyqt ? and how ? i've been trying to find an answer for this for 3 days . if you know website or a good place to learn pyqt, it will be highly appreciated thanx in advance

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  • Django: Serving Media Behind Custom URL

    - by TheLizardKing
    So I of course know that serving static files through Django will send you straight to hell but I am confused on how to use a custom url to mask the true location of the file using Django. http://stackoverflow.com/questions/2681338/django-serving-a-download-in-a-generic-view but the answer I accepted seems to be the "wrong" way of doing things. urls.py: url(r'^song/(?P<song_id>\d+)/download/$', song_download, name='song_download'), views.py: def song_download(request, song_id): song = Song.objects.get(id=song_id) fsock = open(os.path.join(song.path, song.filename)) response = HttpResponse(fsock, mimetype='audio/mpeg') response['Content-Disposition'] = "attachment; filename=%s - %s.mp3" % (song.artist, song.title) return response This solution works perfectly but not perfectly enough it turns out. How can I avoid having a direct link to the mp3 while still serving through nginx/apache? EDIT 1 - ADDITIONAL INFO Currently I can get my files by using an address such as: http://www.example.com/music/song/1692/download/ But the above mentioned method is the devil's work. How can I accomplished what I get above while still making nginx/apache serve the media? Is this something that should be done at the webserver level? Some crazy mod_rewrite? http://static.example.com/music/Aphex%20Twin%20-%20Richard%20D.%20James%20(V0)/10%20Logon-Rock%20Witch.mp3

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  • PySVN: is property status "none" equivalent to unchanged?

    - by detly
    I know the practical difference between a PySVN property status of "normal" (has properties, not changed locally) and "none" (has no properties). My question is this: is it ever possible for there to be local modifications to an items properites, and have PySVN report the property status as "none"? I would say no, but maybe there's some corner case I'm missing.

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  • Graphing a line and scatter points using Matplotlib?

    - by Patrick O'Doherty
    Hi guys I'm using matplotlib at the moment to try and visualise some data I am working on. I'm trying to plot around 6500 points and the line y = x on the same graph but am having some trouble in doing so. I can only seem to get the points to render and not the line itself. I know matplotlib doesn't plot equations as such rather just a set of points so I'm trying to use and identical set of points for x and y co-ordinates to produce the line. The following is my code from matplotlib import pyplot import numpy from pymongo import * class Store(object): """docstring for Store""" def __init__(self): super(Store, self).__init__() c = Connection() ucd = c.ucd self.tweets = ucd.tweets def fetch(self): x = [] y = [] for t in self.tweets.find(): x.append(t['positive']) y.append(t['negative']) return [x,y] if __name__ == '__main__': c = Store() array = c.fetch() t = numpy.arange(0., 0.03, 1) pyplot.plot(array[0], array[1], 'ro', t, t, 'b--') pyplot.show() Any suggestions would be appreciated, Patrick

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  • Renaming TurboGears 2's Repoze Fields with TGAdmin

    - by William Chambers
    I've been working on renaming TurboGears 2's Repoze 'groups' field to 'roles' to free the namespace and db tables for other purposes. Also roles makes much more sense to me then groups because I have a strong Drupal background. Now I have found some of the docs to do this such as these: http://www.turbogears.org/2.1/docs/main/Auth/Customization.html#customizing-the-model-structure-assumed-by-the-quickstart http://code.gustavonarea.net/repoze.what-quickstart/#customizing-the-model-definition However these only go part of the way. I have made (I'm pretty sure at least, I've double checked a few times.) all the changes required as you can see in this diff. This seems to work fine however I've ran into a rather major issue with the TurboGears Admin system. I've tried http://turbogears.org/2.0/docs/main/Extensions/Admin/index.html and it didn't seem to make any difference, however I'm not 100% sure I did it correctly. The problem occurs when I attempt to go to localhost/admin/permissions/. It causes a Internal Server Error and outputs the following error. http://pastebin.com/YWMH3SiU This error does not happen on the Roles/Users pages and the permissions /edit/1 also works. I'm running kubuntu 10.04 with TG 2.1b2. (I'm running the beta mostly for easier mako support which is really important.) Any help would be very appreciated.

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  • Map only certain parts of the class to a database using SQLAlchemy?

    - by Az
    When mapping an object using SQLAlchemy, is there a way to only map certain elements of a class to a database, or does it have to be a 1:1 mapping? Example: class User(object): def __init__(self, name, username, password, year_of_birth): self.name = name self.username = username self.password = password self.year_of_birth = year_of_birth Say, for whatever reason, I only wish to map the name, username and password to the database and leave out the year_of_birth. Is that possible and will this create problems? Edit - 25/03/2010 Additionally, say I want to map username and year_of_birth to a separate database. Will this database and the one above still be connected (via username)?

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  • How to run unittest under pydev for Django?

    - by photon
    I configured properties for my django project under pydev. I can run the django app under pydev or under console window. I can also run unittest for app under console window. But I have problems to run unittest under pydev. I guess it's something related to run configurations of pydev, so I made several trials, but with no success. Once I got messages like this: ImportError: Could not import settings 'D:\django_projects\MyProject' (Is it on sys.path? Does it have syntax errors?): No module named D:\django_projects\MyProject ERROR: Module: MyUnittestFile could not be imported. Another time I got messages like this: ImportError: Could not import settings 'MyProject.settngs' (Is it on sys.path? Does it have syntax errors?): No module named settngs 'ERROR: Module: MyUnittestFile could not be imported. I use pydev 1.5.6 on eclipse and windows xp. Any ideas for this problem?

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  • Loading Files in AppEngine

    - by Chris M
    I've got a tiny bit of code to display a file in app.yaml - url: /(.*\.(gif|png|jpg)) static_files: static/\1 upload: static/(.*\.(gif|png|jpg)) in main.py ... class ShowImage(webapp.RequestHandler): def get(self): rootpath = os.path.dirname(__file__) file = rootpath + "/static/tracker.gif"; fh=open(file, 'r') self.response.out.write(fh.read()) fh.close ... I can see the files gone up by going to my *.appspot.com/tracker.gif (as per the app.yaml) But using *.appspot.com/showimage returns Traceback (most recent call last): File "/base/python_lib/versions/1/google/appengine/ext/webapp/__init__.py", line 510, in __call__ handler.get(*groups) File "/base/data/home/apps/APPNAME/2.341131266814384624/main.py", line 170, in get fh=open(file, 'r') IOError: [Errno 2] No such file or directory: '/base/data/home/apps/APPNAME/2.341131266814384624/static/tracker.gif'

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  • How to update the contents of a FigureCanvasTkAgg

    - by Copo
    I'm plotting some data in a Tkinter FigureCanvasTkagg using matplotlib. I need to clear the figure where i plot data and draw new data when a button is pressed. here is the plotting part of the code (there's an App class defined before..) self.fig = figure() self.ax = self.fig.add_subplot(111) self.ax.set_ylim( min(y), max(y) ) self.line, = self.ax.semilogx(x,y,'.-') #tuple of a single element self.canvas = FigureCanvasTkAgg(self.fig,master=master) self.ax.semilogx(x,y,'o-') self.canvas.show() self.canvas.get_tk_widget().pack(side='top', fill='both', expand=1) self.frame.pack() how do i update the contents of such a canvas? regards, Jacopo

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  • Problem with eastern european characters when scraping data from the European Parliaments Website

    - by Thomas Jensen
    Dear Experts I am trying to scrape a lot of data from the European Parliament website for a research project. Ther first step is the create a list if all parliamentarians, however due to the many Eastern European names and the accents they use i get a lot of missing entries. Here is an example of what is giving me troubles (notice the accents at the end of the family name): ANDRIKIENE, Laima Liucija Group of the European People's Party (Christian Democrats) So far I have been using PyParser and the following code: parser_names name = Word(alphanums + alphas8bit) begin, end = map(Suppress, "<") names = begin + ZeroOrMore(name) + "," + ZeroOrMore(name) + end for name in names.searchString(page): print(name) However this does not catch the name from the html above. Any advice in how to proceed? Best, Thomas

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  • Rewriting Live TCP Streams

    - by user213060
    I want to rewrite TCP/IP streams. Ettercap's etterfilter command lets you perform simple live replacements of TCP/IP data based on fixed strings or regexes. Example: http://ettercap.sourceforge.net/forum/viewtopic.php?t=2833 I would like to rewrite streams based on my own filter program instead of just simple string replacements. Anyone have an idea of how to do this? Is there anything other than Ettercap that can do live replacement like this, maybe as a plugin to a VPN software or something? Thanks!

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  • Start PyGTK cellrenderer edit from code

    - by mkotechno
    I have a treeview with an editable CellRendererText: self.renderer = gtk.CellRendererText() self.renderer.set_property('editable', True) But now I need to launch the edition from code instead from user, this is to focus the user attention in the fact he just created a new row and needs to be named. I tried this but does not work: self.renderer.start_editing( gtk.gdk.Event(gtk.gdk.NOTHING), self.treeview, str(index), gtk.gdk.Rectangle(), gtk.gdk.Rectangle(), 0) Neither does not throw errors, but the documentation about for what is each argument is not clear, in fact I really don't know if start_editing method is for this. All suggestions are welcome, thanks.

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  • How to get lng lat value from query results of geoalchemy2

    - by user2213606
    For exammple, class Lake(Base): __tablename__ = 'lake' id = Column(Integer, primary_key=True) name = Column(String) geom = Column(Geometry('POLYGON')) point = Column(Geometry('Point')) lake = Lake(name='Orta', geom='POLYGON((3 0,6 0,6 3,3 3,3 0))', point="POINT(2 9)") query = session.query(Lake).filter(Lake.geom.ST_Contains('POINT(4 1)')) for lake in query: print lake.point it returned <WKBElement at 0x2720ed0; '010100000000000000000000400000000000002240'> I also tried to do lake.point.ST_X() but it didn't give the expected latitude neither What is the correct way to transform the value from WKBElement to readable and useful format, say (lng, lat)? Thanks

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  • Polynomial fitting with log log plot

    - by viral parekh
    I have a simple problem to fit a straight line on log-log scale. My code is, data=loadtxt(filename) xdata=data[:,0] ydata=data[:,1] polycoeffs = scipy.polyfit(xdata, ydata, 1) yfit = scipy.polyval(polycoeffs, xdata) pylab.plot(xdata, ydata, 'k.') pylab.plot(xdata, yfit, 'r-') Now I need to plot fit line on log scale so I just change x and y axis, ax.set_yscale('log') ax.set_xscale('log') then its not plotting correct fit line. So how can I change fit function (in log scale) so that it can plot fit line on log-log scale? Thanks -Viral

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  • PyML 0.7.2 - How to prevent accuracy from dropping after stroing/loading a classifier?

    - by Michael Aaron Safyan
    This is a followup from "Save PyML.classifiers.multi.OneAgainstRest(SVM()) object?". The solution to that question was close, but not quite right, (the SparseDataSet is broken, so attempting to save/load with that dataset container type will fail, no matter what. Also, PyML is inconsistent in terms of whether labels should be numbers or strings... it turns out that the oneAgainstRest function is actually not good enough, because the labels need to be strings and simultaneously convertible to floats, because there are places where it is assumed to be a string and elsewhere converted to float) and so after a great deal of hacking and such I was finally able to figure out a way to save and load my multi-class classifier without it blowing up with an error.... however, although it is no longer giving me an error message, it is still not quite right as the accuracy of the classifier drops significantly when it is saved and then reloaded (so I'm still missing a piece of the puzzle). I am currently using the following custom mutli-class classifier for training, saving, and loading: class SVM(object): def __init__(self,features_or_filename,labels=None,kernel=None): if isinstance(features_or_filename,str): filename=features_or_filename; if labels!=None: raise ValueError,"Labels must be None if loading from a file."; with open(os.path.join(filename,"uniquelabels.list"),"rb") as uniquelabelsfile: self.uniquelabels=sorted(list(set(pickle.load(uniquelabelsfile)))); self.labeltoindex={}; for idx,label in enumerate(self.uniquelabels): self.labeltoindex[label]=idx; self.classifiers=[]; for classidx, classname in enumerate(self.uniquelabels): self.classifiers.append(PyML.classifiers.svm.loadSVM(os.path.join(filename,str(classname)+".pyml.svm"),datasetClass = PyML.VectorDataSet)); else: features=features_or_filename; if labels==None: raise ValueError,"Labels must not be None when training."; self.uniquelabels=sorted(list(set(labels))); self.labeltoindex={}; for idx,label in enumerate(self.uniquelabels): self.labeltoindex[label]=idx; points = [[float(xij) for xij in xi] for xi in features]; self.classifiers=[PyML.SVM(kernel) for label in self.uniquelabels]; for i in xrange(len(self.uniquelabels)): currentlabel=self.uniquelabels[i]; currentlabels=['+1' if k==currentlabel else '-1' for k in labels]; currentdataset=PyML.VectorDataSet(points,L=currentlabels,positiveClass='+1'); self.classifiers[i].train(currentdataset,saveSpace=False); def accuracy(self,pts,labels): logger=logging.getLogger("ml"); correct=0; total=0; classindexes=[self.labeltoindex[label] for label in labels]; h=self.hypotheses(pts); for idx in xrange(len(pts)): if h[idx]==classindexes[idx]: logger.info("RIGHT: Actual \"%s\" == Predicted \"%s\"" %(self.uniquelabels[ classindexes[idx] ], self.uniquelabels[ h[idx] ])); correct+=1; else: logger.info("WRONG: Actual \"%s\" != Predicted \"%s\"" %(self.uniquelabels[ classindexes[idx] ], self.uniquelabels[ h[idx] ])) total+=1; return float(correct)/float(total); def prediction(self,pt): h=self.hypothesis(pt); if h!=None: return self.uniquelabels[h]; return h; def predictions(self,pts): h=self.hypotheses(self,pts); return [self.uniquelabels[x] if x!=None else None for x in h]; def hypothesis(self,pt): bestvalue=None; bestclass=None; dataset=PyML.VectorDataSet([pt]); for classidx, classifier in enumerate(self.classifiers): val=classifier.decisionFunc(dataset,0); if (bestvalue==None) or (val>bestvalue): bestvalue=val; bestclass=classidx; return bestclass; def hypotheses(self,pts): bestvalues=[None for pt in pts]; bestclasses=[None for pt in pts]; dataset=PyML.VectorDataSet(pts); for classidx, classifier in enumerate(self.classifiers): for ptidx in xrange(len(pts)): val=classifier.decisionFunc(dataset,ptidx); if (bestvalues[ptidx]==None) or (val>bestvalues[ptidx]): bestvalues[ptidx]=val; bestclasses[ptidx]=classidx; return bestclasses; def save(self,filename): if not os.path.exists(filename): os.makedirs(filename); with open(os.path.join(filename,"uniquelabels.list"),"wb") as uniquelabelsfile: pickle.dump(self.uniquelabels,uniquelabelsfile,pickle.HIGHEST_PROTOCOL); for classidx, classname in enumerate(self.uniquelabels): self.classifiers[classidx].save(os.path.join(filename,str(classname)+".pyml.svm")); I am using the latest version of PyML (0.7.2, although PyML.__version__ is 0.7.0). When I construct the classifier with a training dataset, the reported accuracy is ~0.87. When I then save it and reload it, the accuracy is less than 0.001. So, there is something here that I am clearly not persisting correctly, although what that may be is completely non-obvious to me. Would you happen to know what that is?

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  • Google App Engine + Form Validation

    - by Iwona
    Hi, I would like to do google app engine form validation but I dont know how to do it? I tried like this: from google.appengine.ext.db import djangoforms from django import newforms as forms class SurveyForm(forms.Form): occupations_choices = ( ('1', ""), ('2', "Undergraduate student"), ('3', "Postgraduate student (MSc)"), ('4', "Postgraduate student (PhD)"), ('5', "Lab assistant"), ('6', "Technician"), ('7', "Lecturer"), ('8', "Other" ) ) howreach_choices = ( ('1', ""), ('2', "Typed the URL directly"), ('3', "Site is bookmarked"), ('4', "A search engine"), ('5', "A link from another site"), ('6', "From a book"), ('7', "Other") ) boxes_choices = ( ("des", "Website Design"), ("svr", "Web Server Administration"), ("com", "Electronic Commerce"), ("mkt", "Web Marketing/Advertising"), ("edu", "Web-Related Education") ) name = forms.CharField(label='Name', max_length=100, required=True) email = forms.EmailField(label='Your Email Address:') occupations = forms.ChoiceField(choices=occupations_choices, label='What is your occupation?') howreach = forms.ChoiceField(choices=howreach_choices, label='How did you reach this site?') # radio buttons 1-5 rating = forms.ChoiceField(choices=range(1,6), label='What is your occupation?', widget=forms.RadioSelect) boxes = forms.ChoiceField(choices=boxes_choices, label='Are you involved in any of the following? (check all that apply):', widget=forms.CheckboxInput) comment = forms.CharField(widget=forms.Textarea, required=False) And I wanted to display it like this: template_values = { 'url' : url, 'url_linktext' : url_linktext, 'userName' : userName, 'item1' : SurveyForm() } And I have this error message: Traceback (most recent call last): File "C:\Program Files\Google\google_appengine\google\appengine\ext\webapp_init_.py", line 515, in call handler.get(*groups) File "C:\Program Files\Google\google_appengine\demos\b00213576\main.py", line 144, in get self.response.out.write(template.render(path, template_values)) File "C:\Program Files\Google\google_appengine\google\appengine\ext\webapp\template.py", line 143, in render return t.render(Context(template_dict)) File "C:\Program Files\Google\google_appengine\google\appengine\ext\webapp\template.py", line 183, in wrap_render return orig_render(context) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 168, in render return self.nodelist.render(context) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 705, in render bits.append(self.render_node(node, context)) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 718, in render_node return(node.render(context)) File "C:\Program Files\Google\google_appengine\lib\django\django\template\defaulttags.py", line 209, in render return self.nodelist_true.render(context) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 705, in render bits.append(self.render_node(node, context)) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 718, in render_node return(node.render(context)) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 768, in render return self.encode_output(output) File "C:\Program Files\Google\google_appengine\lib\django\django\template_init_.py", line 757, in encode_output return str(output) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\util.py", line 26, in str return self.unicode().encode(settings.DEFAULT_CHARSET) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\forms.py", line 73, in unicode return self.as_table() File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\forms.py", line 144, in as_table return self._html_output(u'%(label)s%(errors)s%(field)s%(help_text)s', u'%s', '', u'%s', False) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\forms.py", line 129, in _html_output output.append(normal_row % {'errors': bf_errors, 'label': label, 'field': unicode(bf), 'help_text': help_text}) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\forms.py", line 232, in unicode value = value.str() File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\util.py", line 26, in str return self.unicode().encode(settings.DEFAULT_CHARSET) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\widgets.py", line 246, in unicode return u'\n%s\n' % u'\n'.join([u'%s' % w for w in self]) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\widgets.py", line 238, in iter yield RadioInput(self.name, self.value, self.attrs.copy(), choice, i) File "C:\Program Files\Google\google_appengine\lib\django\django\newforms\widgets.py", line 212, in init self.choice_value = smart_unicode(choice[0]) TypeError: 'int' object is unsubscriptable Do You have any idea how I can do this validation in different case? I have tried to do it using this kind of: class ItemUserAnswer(djangoforms.ModelForm): class Meta: model = UserAnswer But I dont know how to add extra labels to this form and it is displayed in one line. Do You have any suggestions? Thanks a lot as it making me crazy why it is still not working:/

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  • Why do I get rows of zeros in my 2D fft?

    - by Nicholas Pringle
    I am trying to replicate the results from a paper. "Two-dimensional Fourier Transform (2D-FT) in space and time along sections of constant latitude (east-west) and longitude (north-south) were used to characterize the spectrum of the simulated flux variability south of 40degS." - Lenton et al(2006) The figures published show "the log of the variance of the 2D-FT". I have tried to create an array consisting of the seasonal cycle of similar data as well as the noise. I have defined the noise as the original array minus the signal array. Here is the code that I used to plot the 2D-FT of the signal array averaged in latitude: import numpy as np from numpy import ma from matplotlib import pyplot as plt from Scientific.IO.NetCDF import NetCDFFile ### input directory indir = '/home/nicholas/data/' ### get the flux data which is in ### [time(5day ave for 10 years),latitude,longitude] nc = NetCDFFile(indir + 'CFLX_2000_2009.nc','r') cflux_southern_ocean = nc.variables['Cflx'][:,10:50,:] cflux_southern_ocean = ma.masked_values(cflux_southern_ocean,1e+20) # mask land nc.close() cflux = cflux_southern_ocean*1e08 # change units of data from mmol/m^2/s ### create an array that consists of the seasonal signal fro each pixel year_stack = np.split(cflux, 10, axis=0) year_stack = np.array(year_stack) signal_array = np.tile(np.mean(year_stack, axis=0), (10, 1, 1)) signal_array = ma.masked_where(signal_array > 1e20, signal_array) # need to mask ### average the array over latitude(or longitude) signal_time_lon = ma.mean(signal_array, axis=1) ### do a 2D Fourier Transform of the time/space image ft = np.fft.fft2(signal_time_lon) mgft = np.abs(ft) ps = mgft**2 log_ps = np.log(mgft) log_mgft= np.log(mgft) Every second row of the ft consists completely of zeros. Why is this? Would it be acceptable to add a randomly small number to the signal to avoid this. signal_time_lon = signal_time_lon + np.random.randint(0,9,size=(730, 182))*1e-05 EDIT: Adding images and clarify meaning The output of rfft2 still appears to be a complex array. Using fftshift shifts the edges of the image to the centre; I still have a power spectrum regardless. I expect that the reason that I get rows of zeros is that I have re-created the timeseries for each pixel. The ft[0, 0] pixel contains the mean of the signal. So the ft[1, 0] corresponds to a sinusoid with one cycle over the entire signal in the rows of the starting image. Here are is the starting image using following code: plt.pcolormesh(signal_time_lon); plt.colorbar(); plt.axis('tight') Here is result using following code: ft = np.fft.rfft2(signal_time_lon) mgft = np.abs(ft) ps = mgft**2 log_ps = np.log1p(mgft) plt.pcolormesh(log_ps); plt.colorbar(); plt.axis('tight') It may not be clear in the image but it is only every second row that contains completely zeros. Every tenth pixel (log_ps[10, 0]) is a high value. The other pixels (log_ps[2, 0], log_ps[4, 0] etc) have very low values.

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  • Infrastructure for a "news-feed"

    - by ensnare
    I'd like to offer a news-feed like feature for users of our website. When the user logs in, he is shown a list of the latest updates across various areas of the site. I'm afraid that this is going to be difficult to scale. What are some networking / database topologies that can support a scalable infrastructure without having lots of copies of the same data? (I'd like to make it so if a piece of data is updated, each user's feed is also updated live). Thanks for the assistance and advice.

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